Dehydroepiandrosterone (DHEA) and its sulfate derivative are major adrenal secretory products in humans, yet no biological function for DHEA has been definitely established. Decreased secretion of DHEA has been associated with advancing age in both sexes, and with certain types of breast cancer in women. Chronic treatment with DHEA in the diet has been shown to increase longevity in rodents by retarding the development of specific diseases associated with particular strains or mutants. Thus, ameliorative biological effects have been established relating to obesity, tumor development, aging, and immune function. The steroid DHEA appears to have many of the beneficial effects of caloric restriction without actually decreasing the amount of food eaten. Popular articles have appeared documenting the interest in DHEA as a potential weapon against obesity, cancer and the aging process, for example, Rosenfeld, "The Re-examination of a Curious Hormone", Science 81, 20 and 24 (November, 1981), and Rosenfeld, "Superpowder", Omni, 59, 60, 110 and 112 (August, 1982). However, prior to the work of the present inventors, no one has ever found or established a beneficial effect of DHEA as an anti-diabetic or anti-hyperglycemic agent. In fact, certain studies reported no correlation with blood sugar. The full correct chemical name for DHEA is androst-5-ene-3.beta.-ol-17-one.
British Patent Specification No. 1,246,639 describes the manufacture and use of dehydroepiandrosterone esters for the treatment of menopause and symptoms and complaints associated with menopause, without androgenic side effects or virilisation phenomena. The ester is formed, for example, by reacting the DHEA with an acid such as an acid anhydride or acid halide in the presence of pyridine. U.S. Pat. No. 3,963,707 describes a variety of steroid compounds having anti-tumor activity. The patent describes methods for preparation of such compounds for inhibiting the growth of tumors. Among the steroid hormones mentioned for use in the compound preparation described in this patent is DHEA. U.S. Pat. No. 4,042,459 is of only related interest and describes the use of microbial transformation to selectively degrade steroids including DHEA. No references prior to the inventors' own work has suggested, discovered, established or found a utility for DHEA in the treatment of diabetes.